Just a quick post to document the locations of the ROM's under the PSU.. I find it confusing what ROM goes where, so here's where they all go!

Some older machines have 6 chip TOS installed. Generally I would recommend using one of my TOS adapters and upgrading to TOS104. However on some machines it is not always possible.

As there are 2 basic versions of TOS location , here is a conversion. The left numbers are taken with TOS under the PSU. The last numbers are TOS located on the left of the motherboard. Also see images below.